Virulence Characteristics and Molecular Typing of Carbapenem-Resistant ST15 <i>Klebsiella pneumoniae</i> Clinical Isolates, Possessing the K24 Capsular Type

• Main Authors: Marianna Horváth (Author), Tamás Kovács (Author), József Kun (Author), Attila Gyenesei (Author), Ivelina Damjanova (Author), Zoltán Tigyi (Author), György Schneider (Author)
• Format: Book
• Published: MDPI AG, 2023-02-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

<i>Klebsiella pneumoniae</i> is an opportunistic pathogen that frequently causes nosocomial and community-acquired (CA) infections. Until now, a limited number of studies has been focused on the analyses of changes affecting the virulence attributes. Genotypic and phenotypic methods were used to characterise the 39 clinical <i>K. pneumoniae</i> isolates; all belonged to the pan-drug resistant, widespread clone ST 15 and expressed the K24 capsule. PFGE has revealed that the isolates could be divided into three distinct genomic clusters. All isolates possessed <i>allS</i> and <i>uge</i> genes, known to contribute to the virulence of <i>K. pneumoniae</i> and 10.25% of the isolates showed hypermucoviscosity, 94.87% produced type 1 fimbriae, 92.3% produced type 3 fimbriae, and 92.3% were able to produce biofilm. In vivo persistence could be supported by serum resistance 46.15%, enterobactin (94.87%) and aerobactin (5.12%) production and invasion of the INT407 and T24 cell lines. Sequence analysis of the whole genomes of the four representative strains 11/3, 50/1, 53/2 and 53/3 has revealed high sequence homology to the reference <i>K. pneumoniae</i> strain HS11286. Our results represent the divergence of virulence attributes among the isolates derived from a common ancestor clone ST 15, in an evolutionary process that occurred both in the hospital and in the community.

Item Description

10.3390/antibiotics12030479
2079-6382